Are you meaning a UVB100? Fire bellied toads are active during the day and bask. I have kept them with and without and they do much better with it. Remember a lot of online care sheets are bad or outdated. They will live without UVB or a basking spot but it's not the best husbandry, we can do better. The UVB100 (which is a 5% UVB, the lowest effective lamp when placed over screen) should be fine in most cases.
There is a lot of conflicting information on many aspects of their care but I have found the books Amphibians in Captivity by Marc Staniszewski and Popular Amphibians by Philippe de Vosjoli to be good authorities. Here's some links that will help:
http://www.ncbi.nlm.nih.gov/pubmed/24810567
http://www.exo-terra.com/en/explore/uv_rating_index.php
http://www.arcadia-reptile.com/wp-co...belly-toad.jpg
http://www.amphibian.co.uk/bombina.html